Demodicosis

Demodicosis 

Demodicosis, commonly known as demodectic mange, is a parasitic skin disease in dogs caused by microscopic mites called Demodex canis that live naturally in the hair follicles and oil glands of the skin. While a small number of these mites are normal and harmless, demodicosis develops when the dog’s immune system becomes weakened or unbalanced, allowing the mites to multiply excessively and cause inflammation, hair loss, and skin infections. The condition is not contagious to humans or other animals and can affect dogs of any age, though it is most common in puppies, young adults, and dogs with compromised immunity.

Demodicosis in dogs occurs in two main forms — localised and generalised. Localised demodicosis typically affects small patches of skin, especially on the face, around the eyes, mouth, or legs. It often appears as circular areas of hair loss, redness, and mild scaling, and in many cases, it can resolve on its own as the dog’s immune system matures. On the other hand, generalised demodicosis is more serious and widespread, affecting large portions of the body and sometimes involving secondary bacterial or yeast infections. This form often requires medical treatment and long-term management.

The causes of demodicosis are closely linked to immune suppression or genetic predisposition. Stress, poor nutrition, hormonal disorders, prolonged illness, or the use of immunosuppressing drugs such as corticosteroids can trigger mite overgrowth. Some breeds, including Bulldogs, Boxers, Shar-Peis, and German Shepherds, are believed to have a hereditary susceptibility to demodectic mange. Puppies can also acquire mites from their mother through direct contact during nursing, though they only develop disease if their immune response fails to control mite populations.

Symptoms of demodicosis in dogs vary depending on the severity of the infestation. Common signs include hair loss, red or flaky skin, thickened or crusty patches, and itching (though itching may be mild in early stages). In generalised cases, dogs may show greasy skin, a foul odour, pustules, and severe itching due to secondary infections. The paws, face, and neck are often affected first, and chronic cases can lead to darkened, thickened skin and widespread discomfort.

Veterinarians diagnose demodicosis through skin scraping or hair-plucking tests viewed under a microscope to identify Demodex mites. In some resistant or deep cases, a skin biopsy may be needed for confirmation. Your vet may also perform additional tests to check for underlying immune or hormonal disorders such as hypothyroidism or Cushing’s disease, which can worsen the condition.

Treatment for demodicosis in dogs depends on the extent and type of infection. Localised cases often resolve without medication, but generalised or chronic infections require prescribed miticidal treatments such as amitraz dips, ivermectin, milbemycin oxime, or newer isoxazoline drugs like fluralaner (Bravecto), afoxolaner (NexGard), or sarolaner (Simparica). These medications kill mites and help restore healthy skin. In addition, antibiotics, medicated shampoos, and omega-3 supplements are often used to treat secondary infections and promote healing. Dogs with generalised demodicosis may need months of continuous therapy and regular skin rechecks until two consecutive negative skin scrapings confirm that mites are eliminated.

Good home care and nutrition play a vital role in recovery. Feeding a balanced diet, managing stress, maintaining hygiene, and avoiding unnecessary steroids help strengthen immunity. Regular grooming and bathing with gentle, antibacterial shampoos can reduce inflammation and prevent infection. For breeding dogs, those with a hereditary form of demodicosis should not be bred, as the condition can be passed to offspring.

With early detection and proper veterinary care, most dogs with demodicosis recover fully and go on to live healthy lives. However, neglecting treatment or failing to manage underlying health issues can lead to recurrent flare-ups and chronic skin problems. Routine skin checks and consistent parasite prevention are the best ways to protect your pet from dog skin mites and ensure a shiny, healthy coat.